• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.291-298
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• 2001

Seawater, sediment and biota in the Kwangyang Bay were analyzed by gas chromatography/quartz furnace atomic absorption spectroscopy (GC-QFAAS) to investigate concentrations and distribution pattern of butyltin compounds (TBT, DBT, MBT) during February, April and July, 1996, Marine biota analyzed were Tapes japcnicus and Crassostrea gigas. The concentrations of tributyltin (TBT) in seawater were in the range of ND-15.7 ng/L for the surface and ND-68.5 ng/L for the bottom. The highest concentration of TBT in seawater was detected in April for the both, surface and bottom water. The maximum value of $TBT_{(bottom)}/TBT_{(surface)}$, 3.6 in April showed the increased input of TBT from the surface water in April compared to February (2.1) and July (0.9). The concentrations of TBT in the sediment were in the range of ND-8.5 ng/g dry wt. The highest concentration of TBT in the sediment was measured in July, This result seems to attributed to the removal of TBT from water column via sorption onto particulate matters to the relatively undisturbed underlying sediment and increased input of TBT by increased fluxes of detritus of marine plankton after spring bloom, in July. The mean values of partitioning coefficient ($K_d$) of TBT between seawater and sediment were $3.0\times10^3$(February), $7.4\times10^3$(April) and $9.4\times10^3$(July). The concentrations of TBT in biosamples were in the range of ND-93.30 ng/g dru wt. (T. japonicus) and ND-138.53 ng/g dry wt. (C. gigas). The seasonal variation of TBT contents in biota was remarkable. The $K_d$ (biological concentration factor) was $7-41\times10^3$ for T. japonicus. and $5-34\times10^3$ for C. gigas. The measured TBT concentrations in seawater in the study area was sufficient to cause the imposex of shellfish and to retard the growth of aquatic organisms including oyster upon chronic exposure.

• Progress in Medical Physics
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• v.20 no.1
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• pp.21-29
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• 2009

Breast cancer is the most common form of cancer among korean woman. Therefore, the early detection activities of breast cancer such as breast self-examinations, clinical breast examinations, mammography are important. A yearly mammography examination has been recommended for women aged 40 and older for the early detection of breast cancer in asymptomatic periods. However, the glandular tissue of breast is the most radiation-sensitive tissue, and the determination of average glandular dose (AGD) forms an important part of the quality control of the mammographic systems. Because of the difficulty of estimating AGD directly, it is often estimated from the measurements of the incident air kerma and by applying the appropriate conversion factors. The primary objective of this study was to standardize the method of measuring AGD. The secondary objective was to evaluate the relationships between AGD per various composition and thickness of the breast using Monte Carlo simulations. As a result, we standardized the method of measuring AGD according to International Atomic Energy Agency (IAEA) guidelines (CoP: an international code of practice). Overall, AGD for mammographic practice in Korea was less than 3.0 mGy recommended by the Korea Food and Drug Adminstration (KFDA) protocol, and Korean Institute for Accreditation of Medical Image (KIAMI). The measured and simulated AGD for a given condition were calculated as 1.7 and 1.6 mGy, respectively. For the AGDs obtained, there was no significant difference between them. The simulated AGD was dependent on the fraction of glandular tissue of the breast. The AGD increases with increasing of the breast glandularity due to increasing absorption of low energy photons. The AGD also increases as a function of breast thickness. In conclusion, the results of this study could be used as a baseline to establish a reference level of radiation dose in mammography.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.535-541
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• 2010

Excessive intake of sodium is known as a risk factor for hypertension, and Korean adults consume sodium 3 times higher than Dietary Reference Intakes (DRIs). The purpose of this study was to evaluate the difference on sodium content between analyzed and estimated by food composition table and food exchange list. Seven days of low salt diet and seven days of high salt diet were prepared, and sodium contents were estimated by food composition table and food exchange list and measured by atomic absorption spectrophotometer. Sodium contents of diet per day estimated by food exchange list significantly differed from analyzed content, but those estimated by food composition table were not. However, when absolute differences from analyzed content were compared by dishes in the low and high salt diet periods, there were significant differences among estimated sodium content by food composition table and food exchange list and analyzed sodium content. The discrepancy between those results was due to that absolute value was used to compare sodium contents of dishes but not to compare sodium contents of days. In addition, main dish, side dish, and soup were significantly different among estimated sodium content by food composition table and food exchange list and analyzed sodium content. Actual sodium contents of Jap-Chae Deop-Bap and Roasted chicken with oyster sauce differed to a great extent from estimated contents by food exchange list and food composition table. In conclusion, actual sodium contents of Korean dishes were significantly different from those estimated by food composition table and food exchange list, and thus these differences in salt content should be considered on planning of low-salt menu for hypertensive patients.

• Journal of Radiation Protection and Research
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• v.38 no.2
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• pp.78-90
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• 2013

Recently, the interest on exposure to radiation is rising. The radiation exposure of mammography is higher in absorbed dose than of X-ray, therefore unnecessary exposure needs to be reduced, and higher image quality is needed. Generally, ray quality of the radiation imaging is an important factor that determines image quality and the amount of ray exposure, and they are affected by tube voltage and added filter. The X-ray energy that is exposed from mammography device is generally a continuous spectrum, which includes low energy that has minute influence on the image quality, and high energy that hinders contrast on image. Currently, molybdenum (Mo) and rhodium (Rh) are the most used added filters for mammography device, and they are used differently according to the energy region of X-ray. This study aims to find out the degree of reduction in exposure dose according to the thickness of aluminum (Al), and to study the changes in image quality and dose when the added filter plates that are made with niobium (Nb) or zirconium (Zr) are used, other than molybdenum (Mo) and rhodium (Rh), the two most used added filters that have similar atomic number and K-absorption regions as Nb and Zr. In this study, single-added filters of molybdenum (Mo), niobium (Nb), and zirconium (Zr) are used, and in some cases, Aluminum (Al) is combined with the single filters. In this case, image quality is considered to be improved depending on the type of added filters, and by using Aluminum (Al) filter together with the others, unnecessary X-ray of low energy would be absorbed, therefore the dose is expected to decrease without any influence when the concentration level becomes identical.

• Journal of Yeungnam Medical Science
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• v.15 no.2
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• pp.224-236
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• 1998

A study was conducted to investigate the blood lead and zinc protoporphyrin(ZPP) concentrations of the underground parking lot workers who exposed to vehicular exhaust aerosols which contained lead. The blood samples were collected from 25 study subjects of underground parking lot and from 33 controls in Taegu, from July to October, 1997. And also the related factors to the blood lead and ZPP concentrations were investigated. Blood lead concentration and ZPP concentration were measured by flameless furnace atomic absorption spectrophotometer (1L.551) and hemetofluorometer, respectively. The mean blood lead concentrations of study subjects and controls were $23.10{\pm}20.77{\mu}g/dl$ and $12.99{\pm}12.71{\mu}g/dl$, respectively(p<0.05), and the mean blood ZPP concentrations of study subjects and controls were $40.72{\pm}9.46{\mu}g/dl$ and $38.21{\pm}10.97{\mu}g/dl$, respectively. No significant correlations were observed between the blood lead concentration of the study subjects and their job duration and between blood ZPP concentration of the study subjects and their job duration. There were no statistically significant differences in the blood lead concentration and the blood ZPP concentration of smokers and nonsmokers. In multiple regression analysis on blood lead concentration of the study subjects and controls, occupation was a only significant dependent variable. In case of bood ZPP concentration, age was a only significant dependent variable in the study subjects and controls.

• Journal of agricultural medicine and community health
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• v.21 no.1
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• pp.85-95
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• 1996

To examine the contamination in Ulsan coastal area, some heavy metal concentrations in sea water and Mytilus coruscus have been measured. Sea water samples were collected on April 6 in 1995 and Mytilus coruscus samples were collected on April 2 in 1995. Total number of sea water samples was 26 and that of Mytilus coruscus was 54. The sites where the samples collected were same in sea water and Mytilus coruscus. The method of analysis was atomic absorption spectrophotometer. The results indicated that the heavy metal concentrations of sea water were varied according to the sampling stations. The concentrations of cadmium, manganese, zinc in sea water collected in the coastal area near Mipo complex were higher than those of other coastal areas, and the concentrations of lead in sea water collected in the coastal area near petrochemical complex were higher than those of others. In general the concentrations of lead, zinc, copper in sea water were proportionate to those in Mytilus coruscus. The mean concentration rates of lead, cadmium, manganese in Mytilus coruscus inhabiting in Ulsan coastal area were similar, 1070, 1370 and 1300, respectively. The concentration rate of mercury was 80, the lowest value of other heavy metals, and that of copper was 6940, the highest value. Consequently it seems to be more desirable to use Mytilus coruscus as a sample to examine the contamination of coastal area than sea water.

• Korean Journal of Environmental Agriculture
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• v.11 no.3
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• pp.185-193
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• 1992

To investigate differences in lead content in soils and paddy rices, affected by air pollutants from the Janghang Smelter, soil samples at the different directions, distances, and depths, surface(0-15cm depth) and subsurface(15-30cm depth) in 1982 and 1990, and rice plants at soil sampling sites in 1990 were separately collected at the Janghang Smelter area affected by combustible waste gas from the smelter chimney. Soil samples were extracted with $4M-HNO_3$ and plant samples were digested with mixture of $HNO_3$ and $HCIO_4$ for analyzing by atomic absorption spectrophotometry. The Pb contents in soils ranged from 10.3 to 644.8mg $kg^{-1}$. The average content in 1990 was higher than that in 1982. The Pb content in soils at sites nearer the center of the smelter was higher than that at sites farther from the center. The highest lead content was found at the east direction, and was low in order of east>north-north east>north east > north. The variation of Pb level in soils at east sites was more considerable than other directions. The Pb level in surface soils was higher than that in subsurface soils. The contaminated radius of Pb was until 3km all at east, north-north east and north east. A significant correlation was found between Pb content in surface soils of 1982 and that in surface soils of 1990, between Pb content in soils and contents of Cd and Zn in soils, and between Pb content in soils and soil properties as organic matter, available silicate, cation exchange capacity, exchangeable $Ca^{++}$, $Mg^{++}$ and $Na^+$. Pb content in brown rice was low in the panicle axis, and brown rice, and Pb content in stem was 3.26 times of that in brown rice. Pb content in brown rice ranged from 2.2 to 9.0 mg $kg^{-1}$.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.2
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• pp.116-121
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• 1989

An experiment on movements of copper in soils was conducted to evaluate the effectiveness of several soil extractants in predicting to be possibly the plant availability of copper in soils. Soil samples were taken six, from Las Virgines loam that the samples naturally included high contents of heavy metals near Los Angeles, Greenfield sandy loam and IDomino Loam that received 22.5, and $45.0mg.\;ha^{-1},\;yr^{-1}$ of composted sludge from Los Angeles from 1975 to 1983, respectively. Copper in soils were extracted with $4M\;HNO_3$, 0.1M HCl, 0.5M DTPA-0.1M TEA, 0.5M EDTA-0.1M $Ca(NO_3)_2$, and 1M ammonium acetate(pH 7), and analyzed by atomic absorption spectroscopy. The results were as follows: 1. The total copper contents in soil that received $45.0mg.\;ha^{-1},\;yr^{-1}$ of composted sludge were higher than that received $22.5mg.\;ha^{-1}.yr^{-1}$, regardless of soil samples. 2. The ratios of extractable copper contents with EDTA, DTPA, 0.1M HCl and 1M ammonium acetate to total copper contents extracted with 4M $HNO_3$ of long-term sludge applications were larger than those of natural, sludge-nontreated soils. 3. Statistically significant increase in total copper contents was found in the increasing values of multipling CEC, or OM% by R, ratio of extractable copper contents to those by 4M $HNO_3$ extraction as total copper contents in soils.

• Journal of Food Hygiene and Safety
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• v.20 no.2
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• pp.83-88
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• 2005

This study was conducted to estimate the contents of heavy metals including lead, cadmium, zinc, copper as well as iron status(serum iron, total iron binding capacity, feritin etc)in blood samples of middle school students(n=300). The contents of heavy metals were determined using the GF-AAS (Graphite furnace Atomic Absorption Spectrophotometer). The microwave digestion method and dilution method were compared. The dilution method showed the better recovery and detection limit than microwave digestion method. The values of toxic metals in whloe blood of boys & girls were 3.46 & 3.05 for Pb,0.063 & 0.065 for Cd respectively (ug/dL). Also the values of trace metals in serum of boys & girls were 105.9 & 92.6 for Zn, 98.3 & 99.0 for Cu respectively (ug/dL). The prevalence of iron deficiency was $7.5\%$ in 146 boys and $14.3\%$ in 156 girls. The mean values of lead in girls were higher in iron deficiency, iron deficiency anemia and anemia groups than normal group. The mean values of lead and zinc were higher in boys compared to those in girls(P<0.05), the mean values of cadmium and copper in boys were similar to those in girls. Our results of toxic metals such as Pb & Cd showed lower to CDC's(Centers for Disease Control) blood lead levels of concern for children, 10 ug/dL.

• Journal of agricultural medicine and community health
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• v.22 no.2
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• pp.215-223
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• 1997

To estimate association of minerals relating to non-insulin dependent diabetes mellitus(NIDDM) the contents of essential minerals and toxic heavy metals in the scalp hair were measured during the period from March 1993 to June 1993. The cases were selected 69 (32 male, 37 female) from the patients who visited Kyungpook University Hospital during the period from March 1993 to June 1993 and 74 controls (47 male 27 female) from normal population. zinc, copper, manganese, lead, cadmium and aluminum were analyzed by atomic absorption spectrophotometer(IL. 551). The results were summarized as follows. In NIDDM group, mean contents of zinc and copper were $132.99{\pm}19.66$ ppm, $8.58{\pm}5.07$ ppm respectively; where as $152.51{\pm}46.15$ ppm, $12.48{\pm}6.56$ ppm in control group. The mean of above two mineral content showed significant difference statistically (p<0.01). But, in manganese the content of NIDDM group; $0.44{\pm}0.27$ ppm were significantly higher than the control group; $0.34{\pm}0.18$ ppm(p<0.05). A thesis submitted to the Council of the Graduate School of Kyungpook National University in partial fulfillment of the require ements for the degree of Ph.D. in Medical Science in June 1994. The mean contents of toxic metals - lead, cadmium, aluminum - in NIDDM group were $10.04{\pm}4.60$ ppm, $0.57{\pm}0.12$ ppm, $11.31{\pm}3.98$ ppm; whereas $8.10{\pm}2.45$ ppm, $0.41{\pm}0.23$ ppm, $7.61{\pm}4.16$ ppm in control group. The mean of above three mineral showed significant difference statistically(p<0.01). Cadmium, zinc and copper were selected statistically significant variables with presence of the NIDDM by multiple logistic regression analysis; copper, zinc and cadmium may be associated with NIDDM.